City flushing lines despite restrictions

Posted: Friday, July 06, 2007

A fire hydrant off old U.S. Highway 29 west of Statham has gushed hundreds of gallons of water a day into nearby woods over the past couple of weeks despite an ongoing drought that mostly bans outdoor watering, but the purge is necessary to protect public health, according to water system managers.

The hydrant is near the end of the city of Winder's water lines, which end outside Statham - and at dead-end places like that, old water must be flushed to make sure the water remaining in the line is safe to drink, explained Thomas Taylor, manager of the City of Winder Water Department.

When the chlorine level gets below a state-set minimum, the water could become contaminated with bacteria, so it must be flushed, Taylor said. The flushing gets rid of the potentially unsafe water and draws more recently treated water with higher chlorine levels into the lines, he said.

All water systems have such spots that must be flushed frequently - even more often in summer, when heat accelerates the breakdown of the chlorine in the water, said Myron Garrett, director of the Barrow County Water and Sewerage Authority.

The farther water transmission lines carry water from a treatment plant, the lower the chlorine levels fall, so water system managers have to do a kind of balancing act, making sure chlorine levels are high enough coming out of the treatment plant to ensure protection miles away down the water lines. At the same time, the water can't have too much chlorine at the beginning, because that can pose a different set of health concerns, Garrett said.

It's not unusual for water system managers to flush some far-flung lines every day because of the continuous chlorine breakdown, he said.

The process does waste precious water, and water managers say people do call occasionally to ask why they must obey watering restrictions while the water system lets water gush from hydrants.

But the system should lose only a few hundred gallons a day, Taylor said.

The hydrant near Dunaway Massey Homes between Statham and Winder is timed to discharge for less than 10 minutes a day at a rate of abut 50 gallons per minute, Taylor said.

Taylor said chlorine levels are measured at the hydrant every day, one of dozens of places where Winder workers must measure chlorine levels or test for the presence of bacteria in water.